You explained it really well, but I got lost following the discussion in the link. I'm thinking as you say that the suction behind the greater amount of water in the tank makes it work. Maybe it lowers the air pressure there and the water weight becomes equal with the smaller amount of water in the cup exposed to regular air pressure. Maybe the surface tension of water plays a part, like an amoeba with a pseudopod sticking out? The movie The Blob...
Taxes:
The Buckeyes at 13 days old. Butters on the right, Hazel in the middle and I think Peanut on the left.
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Left to right: Popcorn ready to jump, Peanut, Hazel and Butters.
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